1. Field of the Invention
This invention relates to electromagnetic valves of a high speed drive, and more particularly to electromagnetic valves for controlling the opening or closing of, for example, a fuel jet valve.
2. Prior Art
Heretofore, electromagnetic valves of this kind, for example, as disclosed in official gazette of Japanese Patent Laid-open Publication No. 55-26099, an electromagnetic valve is known in which an armature is moved relative to a stator by excitation of an excitation coil provided on the stator.
However, in the foregoing conventional example, due to self inductance of the excitation coil, the excitation electric current moderately rises as shown by the dotted line in FIG. 3, and when the armature reaches a predetermined position, the excitation electric current once decreases once, and thereafter, it moves toward a predetermined value gradually. Accordingly, the generating power becomes gradually larger according to a change of the excitation electric current as shown by the dotted line in FIG. 4. For this reason, the armature is moderately displaced relative to time as shown by the dotted line in FIG. 5, and when reaching a predetermined position at T.sub.2 seconds from an electric current supply start time T.sub.0 to the excitation coil, the high speed response property of the electromagnetic valve is deteriorated which has been a problem.